LAND AND SOIL RESOURCES

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LAND AND SOIL RESOURCES
CONSERVING THE LAND AND SOIL
ENVIRONMENTAL SCIENCE UNIT 1
MRS. SHARPLESS - TEAM E MR. CONRAD - TEAM F
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TYPES OF LAND USE
AGRICULTURE
- LESS THAN 1/3 OF THE EARTHS LAND CAN BE
FARMED. THE REST IS TOO DRY, TOO WET, TOO SALTY,
OR TOO MOUNTAINOUS.
MINING
- REMOVAL OF NONRENEWABLE RESOURCES (IRON,
COPPER, COAL) FROM THE LAND. STRIP MINING
REMOVES THE TOPSOIL TO GET TO THE RESOURCE, AND
UNDERGROUND MINING INVOLVES TUNNELS OR SHAFTS.
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DEVELOPMENT
THE CONSTRUCTION OF BUILDINGS, ROADS, BRIDGES,
DAMS, AND OTHER STRUCTURES.
IN THE USA, AN AREA HALF THE SIZE OF NEW JERSEY
IS DEVELOPED EACH YEAR.
DEVELOPMENT CAN REDUCE AMOUNTS OF USEABLE
FARMLAND AND DESTROY WILDLIFE HABITATS.
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Soil

• Think about a slice of layer cake.
• You find chocolate bits in the first layer.
• You see chopped walnuts in the second layer.
• You have raisins in the third layer.
• Soil is similar. It has layers that contain
  different things.

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SOIL LAYERS
LITTER - THE TOP LAYER OF FERTILE SOIL. MAY
INCLUDE DEAD LEAVES, GRASS, AND OTHER PLANTLIFE.
TOPSOIL - SECOND LAYER OF SOIL. CONTAINS A
MIXTURE OF ROCK FRAGMENTS, NUTRIENTS, WATER, AIR,
AND DECAYING ANIMAL AND PLANT MATTER. IT TAKES A
LONG TIME FOR THIS TO FORM.
SUBSOIL - THIRD LAYER OF SOIL. CONTAINS ROCK
FRAGMENTS, WATER, AND AIR, BUT HAS LESS ANIMAL
AND PLANT MATTER THAN TOPSOIL.
BEDROCK - THE LOWEST SOIL LAYER. THE ROCK THAT
MAKES UP THE EARTHS CRUST.
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Soil
Earthworms
Soil microorganisms
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Soil
Earthworms
Soil microorganisms
Litter
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Soil
Earthworms
Soil microorganisms
Litter
Topsoil
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Soil
Earthworms
Soil microorganisms
Litter
Topsoil
Subsoil
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Soil
Earthworms
Soil microorganisms
Litter
Topsoil
Subsoil
Bedrock
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POOR MANAGEMENT OF THE SOIL CAN RESULT IN THREE
PROBLEMS
EROSION

NUTRIENT DEPLETION
DESERTIFICATION
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EROSION
THE PROCESS BY WHICH WATER, WIND, OR ICE MOVES
PARTICLES OF ROCKS OR SOIL.
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THESE FARMING PRACTICES CAN HELP REDUCE SOIL
EROSION.
EROSION
1. STRIP CROPPING AND CONTOUR PLOWING
2. CONSERVATION PLOWING
3. WINDBREAKS
4. TERRACING
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NUTRIENT DEPLETION
SOME PLANTS USE MORE NUTRIENTS THAN CAN BE
REPLACED BY SOIL DECOMPOSERS. NUTRIENTS IN SOIL
RUN OUT.
FARMERS MUST ADAPT TO THIS PROBLEM IN MANY WAYS.
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SOIL CONSERVATION
THESE FARMING PRACTICES HELP REDUCE NUTRIENT
DEPLETION.
CROP ROTATION - A FARMER PLANTS DIFFERENT CROPS
IN DIFFERENT FIELDS EACH YEAR. SOME CROPS TAKE
NUTRIENTS AND OTHERS PUT BACK NUTRIENTS INTO THE
SOIL.
FALLOW - FARMERS PERIODICALLY LEAVE A FIELD
UNPLANTED WITH CROPS. THIS ALLOWS NUTRIENTS TO
ACCUMULATE AGAIN IN THE SOIL.
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DESERTIFICATION
THE ADVANCE OF DESERTLIKE CONDITIONS INTO AREAS
THAT PREVIOUSLY WERE FERTILE. MOISTURE AND
NUTRIENTS ARE NO LONGER IN THE SOIL.
THREE CAUSES OF DESERTIFICATION ARE CLIMATE
CHANGE (DROUGHTS) , OVERGRAZING OF ANIMALS, AND
CUTTING DOWN TREES (FORESTS). ALL REMOVE PLANTS
FROM THE SOIL --WIND BLOWS SOIL AWAY AND PEOPLE
CAN NO LONGER USE THE LAND.
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RESTORING THE LAND
LAND RECLAMATION - THE PROCESS OF RESTORING AN
AREA OF LAND TO A MORE NATURAL, USEFUL STATE.
RESTORES LAND FOR AGRICULTURE AND WILDLIFE.
RESTORES LAND DAMAGED BY EROSION AND MINING.
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LAND AND SOIL RESOURCES
SOLID WASTE
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TRASH FACTS - USA
THE AVERAGE PERSON PRODUCES ABOUT 2 KILOGRAMS OF
TRASH DAILY.
EVERY HOUR, PEOPLE THROW AWAY 2.5 MILLION PLASTIC
BOTTLES.
EVERY YEAR, PEOPLE THROW AWAY ENOUGH PAPER TO
BUILD A WALL 4 METERS HIGH FROM COAST TO COAST.
EVERY YEAR, PEOPLE THROW AWAY 1.6 BILLION PENS,
2.9 MILLION TONS OF PAPER TOWELS, AND 220 MILLION
CAR TIRES.
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MUNICIPAL SOLID WASTE
THE WASTE MATERIALS PRODUCED IN HOMES,
BUSINESSES, SCHOOLS, AND OTHER COMMUNITY PLACES.
THERE ARE THREE METHODS OF HANDLING SOLID
WASTES..
BURY THE WASTE
BURN THE WASTE
RECYCLE THE WASTE
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LANDFILLS
UNTIL FAIRLY RECENTLY, PEOPLE USUALLY DISPOSED OF
WASTE IN OPEN HOLES IN THE GROUND. THESE OPEN
DUMPS WERE DANGEROUS AND UGLY. RAINWATER SEEPING
INTO THE LANDFILL DISSOLVED CHEMICALS IN THE
WASTE. BIG PROBLEM!!!!
LEACHATE - THE POLLUTED LIQUID THAT FORMS WHEN
RAINWATER DISSOLVES CHEMICALS IN AN OPEN
LANDFILL. CAN BE VERY DANGEROUS IF IT GETS IN
LAKES OR STREAMS OR IN THE GROUNDWATER.
IS THERE A SOLUTION TO THIS PROBLEM?
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SANITARY LANDFILL
IN 1976, WHEN MRS. SHARPLESS WAS ABOUT 6 YEARS
OLD, THE GOVERNMENT BANNED OPEN TRASH DUMPS.
SINCE THEN LANDFILLS ARE MADE TO BE SAFER AND
MORE ENIRONMENTALLY FRIENDLY.
SANITARY LANDFILL - HOLDS MUNICIPAL SOLID WASTE,
CONSTRUCTION DEBRIS, AND SOME TYPES OF
AGRICULTURAL AND INDUSTRIAL WASTE.
EVEN WELL-DESIGNED LANDFILLS STILL POSE RISKS OF
POLLUTING GROUND WATER.
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INCINERATION
THE BURNING OF SOLID WASTE.
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COMPARISON OF LANDFILLS AND INCINERATORS

• INCINERATORS

• Landfills

• Cost

• Pollution

• Attractiveness

• Usefulness to Community

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RECYCLING
THE PROCESS OF RECLAIMING RAW MATERIALS AND
REUSING THEM.
RECYCLING FOCUSES ON FOUR MAJOR CATEGORIES OF
PRODUCTS-- METALS, GLASS, PAPER, AND PLASTICS.
BIODEGRADABLE - A SUBSTANCE THAT CAN BE BROKEN
DOWN AND RECYCLED BY BACTERIA AND OTHER
DECOMPOSERS IN THE GROUND.
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WHAT CAN YOU DO?
USE THE THREE Rs WHEN DEALING WITH SOLID WASTE.
REDUCE
REUSE
RECYCLE
COMPOSTING - SOLID WASTES ARE PLACED IN A
PILE(USUALLY A HOLE DUG IN THE GROUND) TO LET
NATURAL DECOMPOSERS BREAK THEM DOWN. FOOD
WASTES, GRASS CLIPPINGS, LEAVES ARE SOME ITEMS
PUT IN COMPOST PILES.
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LAND AND SOIL RESOURCES
HAZARDOUS WASTES
ENVIRONMENTAL SCIENCE UNIT 1
MRS. SHARPLESS - TEAM E MR. CONRAD - TEAM F
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TYPES OF HAZARDOUS WASTES
HAZARDOUS WASTE - ANY MATERIAL THAT CAN BE
HARMFUL TO HUMAN HEALTH OR THE ENVIRONMENT IF IT
IS NOT PROPERLY DISPOSED OF.
5 TYPES
FLAMMABLE WASTES
TOXIC WASTES
CORROSIVE WASTES
EXPLOSIVE WASTES
RADIOACTIVE WASTES
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TOXIC WASTE
POISONOUS WASTES THAT CAN DAMAGE THE HEALTH OF
HUMANS AND OTHER ORGANISMS.
EXAMPLES OF TOXIC WASTES ARE CHLORINE, PCBs, AND
MERCURY.
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EXPLOSIVE WASTE
WASTES THAT REACT VERY QUICKLY WHEN EXPOSED TO
AIR OR WATER, OR THAT EXPLODE WHEN DROPPED. ALSO
CALLED REACTIVE WASTES.
AN EXAMPLE OF EXPLOSIVE WASTE IS NITROGLYCERIN.
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FLAMMABLE WASTE
WASTES WHICH CATCH FIRE EASILY AND CAN BEGIN
BURNING AT FAIRLY LOW TEMPERATURES.
KEROSENE IS AN EXAMPLE OF FLAMMABLE WASTE.
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CORROSIVE WASTE
WASTES THAT DISSOLVE OR EAT THROUGH MANY
MATERIALS. EXAMPLES OF CORROSIVE WASTES ARE
HYDROCHLORIC ACID (HCl) AND SODIUM HYDROXIDE
(NaOH).
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RADIOACTIVE WASTE
WASTE THAT CONTAINS UNSTABLE ATOMS. THESE
UNSTABLE ATOMS GIVE OFF RADIATION THAT CAN CAUSE
CANCER, CELL DAMAGE, AND OTHER DISEASES.
TWO TYPES OF RADIOACTIVE WASTE
LOW-LEVEL WASTE - PRODUCED IN MEDICAL AND
SCIENTIFIC RESEARCH SITES. BREAKS DOWN RAPIDLY.
HIGH-LEVEL WASTE - PRODUCED FROM USED NUCLEAR
REACTOR FUEL.
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MY HEALTH ?
HOW LONG EXPOSED? AMOUNT OF SUBSTANCE? HOW DID
THE SUBSTANCE ENTER THE BODY?
SHORT- TERM EXPOSURE TO HAZARDOUS WASTES MAY
CAUSE IRRITATION OR MORE SEVERE HEALTH PROBLEMS.
LONG-TERM EXPOSURE MAY CAUSE DISEASES, SUCH AS
CANCER, AND MAY DAMAGE BODY ORGANS, INCLUDING THE
BRAIN, LIVER, KIDNEYS, AND LUNGS.
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HAZARDOUS WASTE
DISPOSAL
- METHODS INCLUDE BURIAL IN LANDFILLS,
INCINERATION, BREAKDOWN BY LIVING ORGANISMS, AND
PUMPING LIQUID WASTES INTO ROCK LAYERS.
- COMPANIES ARE PRODUCING LESS HAZARDOUS
MATERIALS AND ARE SEEKING SAFER ALTERNATIVES.
FOR EXAMPLE, BIODEGRADABLE HOUSE CLEANERS.
REDUCTION